package day0228;

public class charAtDemo {
    public static void main(String[] args) {

        String line = "abcdeglkjpoxcupwjfejlasd";
        String a="";
        for (int i = 0; i < 4; i++) {
            a+=line.charAt((int)(Math.random()*line.length()-1));

        }
        System.out.println(a);
    }
}
